This Study Will Examine the Clinical Effectiveness of Tafamidis in Patients With Mixed Phenotype Hereditary Transthyretin Amyloidosis

Real-World Effectiveness of Tafamidis 80 mg or 61 mg on Neurologic Disease Progression in Patients With Mixed-Phenotype Hereditary Transthyretin Amyloid Cardiomyopathy

This study will examine the clinical effectiveness of Tafamidis in patients with Mixed Phenotype Hereditary Transthyretin Amyloidosis using data that already exist in patients' medical records.

Study Overview

• Status: Completed
• Conditions: Hereditary Transthyretin Amyloidosis (ATTRv) Cardiomyopathy (CM), Mixed Phenotype
• Intervention / Treatment: Drug: tafamidis

Detailed Description

Transthyretin amyloidosis (ATTR amyloidosis) is a rare, life-threatening disease caused by the deposition of transthyretin-derived amyloid fibrils in the peripheral nerves, heart, and other organs. ATTR amyloidosis may arise from mutations in the transthyretin (TTR) gene (ATTRv amyloidosis), or from the aggregation of wild-type TTR (ATTRwt amyloidosis). ATTRv amyloidosis is now widely recognized as a spectrum of disease that can manifest as polyneuropathy, cardiomyopathy, or a mixed phenotype. This non-interventional study will examine the value of high dose tafamidis for delaying neurologic disease progression in mixed-phenotype ATTRv-CM patients.

• Study Type: Observational
• Enrollment (Actual): 10

Contacts and Locations

Study Locations

• United States
  • New York
    • New York, New York, United States, 10017
      • Pfizer

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

The study will include patients with mixed-phenotype ATTRv-CM who are treated in the Amyloidosis Program at MedStar.

Description

Inclusion Criteria:

• Age ≥18 years at diagnosis
• Diagnosed with ATTRv-CM, mixed phenotype
• Treated with tafamidis (VYNDAQEL 80 mg [four 20-mg tafamidis meglumine capsules] orally once daily or VYNDAMAX 61 mg [one 61-mg tafamidis capsule] orally once daily) for ≥6 months
• Have had ≥1 pre- and ≥2 post-treatment neurologic assessments

Exclusion Criteria:

• History of organ transplant
• Wild-type TTR genotype
• Individuals who are non-ambulatory
• Prior treatment with any disease-modifying therapy (investigational or approved) alone or in combination, except tafamidis, as either VYNDAQEL 80 mg (four 20-mg tafamidis meglumine capsules) orally once daily or VYNDAMAX 61 mg (one 61-mg tafamidis capsule) orally once daily
• Peripheral neuropathy attributed to causes other than ATTR amyloidosis (e.g., diabetes mellitus, B12 deficiency, HIV infection)

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Retrospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Patients with mixed phenotype ATTRv-CM; Hereditary ATTR-CM patients presenting with mixed phenotype	Drug: tafamidis; 80 or 61 milligrams (mg); Other Names: Vyndaqel; Vyndamax

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rate of neurologic disease progression	Describe and compare the rate of neurologic disease progression before and after initiation of tafamidis in patients with mixed-phenotype ATTRv-CM receiving tafamidis 80 mg or 61 mg daily in a real-world setting.	Baseline through at least 6 months of treatment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from Baseline in modified Body Mass Index (BMI)	Assess change from BL in mBMI in patients with mixed-phenotype ATTRv-CM receiving 80 mg or 61 mg tafamidis	Baseline (BL) through at least 6 months of treatment

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

Helpful Links

• To obtain contact information for a study center near you, click here.

Study record dates

Study Major Dates

• Study Start (Actual): March 8, 2023
• Primary Completion (Actual): May 19, 2023
• Study Completion (Actual): May 19, 2023

Study Registration Dates

• First Submitted: November 17, 2021
• First Submitted That Met QC Criteria: November 17, 2021
• First Posted (Actual): December 1, 2021

Study Record Updates

• Last Update Posted (Actual): August 9, 2023
• Last Update Submitted That Met QC Criteria: August 8, 2023
• Last Verified: August 1, 2023

More Information

Terms related to this study

• Keywords: amyloidosis; transthyretin; cardiomyopathy; progression; tafamidis; polyneuropathy
• Additional Relevant MeSH Terms: Heart Diseases; Cardiovascular Diseases; Metabolic Diseases; Nervous System Diseases; Genetic Diseases, Inborn; Neuromuscular Diseases; Neurodegenerative Diseases; Peripheral Nervous System Diseases; Proteostasis Deficiencies; Metabolism, Inborn Errors; Heredodegenerative Disorders, Nervous System; Amyloidosis, Familial; Amyloid Neuropathies; Amyloidosis; Cardiomyopathies; Amyloid Neuropathies, Familial
• Other Study ID Numbers: B3461099

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.